(1) Field of the Invention
The invention relates to an air vehicle with a slip protecting and gas sealing composite floor inside a fuselage, the composite floor including at least one profiled elastomer layer provided at its bottom side with a cross-linking agent, one or n-layers of a further component or a variety of further components and partially thermosetting resin covered by the profiled elastomer layer, a honey comb layer and one lower layer or lower n-layers of the further component or a variety of further components and partially thermosetting resin, the honey comb layer being sandwiched between the n-layers and the lower n-layers.
(2) Description of Related Art
Current floor structures for transport aircrafts are either complex and expensive for production or their weight is a significant limitation. The number of different production steps for said floor structures is fairly high. If there is a need for slip protection or for sealing of a fuselage against gases by means of said floor structures expensive and laborious treatment of the floor is needed.
Efficient slip protection requires a detailed knowledge of the slipping process and the mechanisms involved in the reduction of the slipping risk on floors. The most important forces to be considered result from adhesive friction and/or deformation friction:                adhesive friction is dependent on the effective area of contact between the floor, the object on top of the floor (shoe, box etc.) and on the properties of the two materials—a less effective area results in less friction and therefore more risk of slippage,        deformation friction occurs if visco-elastic materials are involved and is dependent on the visco-elastic properties of the materials and the profiles of both surfaces—more visco-elasticity and more profiles result in increased contact area and consequently less risk for slippage        
If there is an intermediate medium involved such as water, ice, mud, oil etc., there is—dependent on the thickness of the layer—a change from adhesive friction to fluid friction, which of course is dependent on the viscosity of the intermediate medium, the area of contact, etc.
National regulations, e.g. German regulations, make assumptions and provide requirements for slip protection at various places and environments. Said regulations could be applied as rules of thumb for slippage protection for floors of transport helicopters and transport aircraft:
For open air pathways without protective roof, loading ramps, and washrooms the German regulations require:                way out space for at least 4 cm3/dm2 liquid on the floor and        no slipping if there is an inclination of the floor of between 10° and 19°.        
For floor panels in aircraft there can be different techniques applied, dependent on the exact requirements: the basic decision is between normal sheets, such as metal or composite, and sandwich structures involving honeycomb components. The exact strength of such a floor panel is dependent—amongst others—on its exact set up, such as material, thickness of layers and honeycomb, etc.
The slip properties of the floor panels are dependent on the material on the top of the floor panels as well as on the roughness/surface structuring.
The following options are realized for different purposes:                resin treated material on top,        metal on top,        glued slip protection foils,        rolled on protection material.        
Disadvantages of Resin Treated Material on Top:                resin treated material normally is very sensitive against any kind of impact during a loading/unloading process. The resin can chip of easily and therefore floor panels made of resin treated material normally have a short lifetime,        the shaping of the surface in order to satisfy the requirements for slip protection above is not easy to realize,        the resin treated material is not visco-elastic and provides no or very low deformation friction        the floor panels need to be painted in an additional process step and        the sealing against gases is independent of slip protection and requires additional efforts.        
Disadvantages of Metal on Top:                if the metal is aluminum, the shaping of the surface in order to satisfy the above mentioned requirements for slip protection requires casting or milling techniques. Said techniques are very time consuming and expensive,        if the metal is iron, the shaping can be done easily but the resulting weight of the floor is fairly high,        the material is not visco-elastic and provides no or very low deformation friction,        if fiber material is involved, the composite structures need to be painted in an additional process step, and        the sealing against gases is independent of slip protection and requires additional efforts.        
Disadvantages of Glued Slip Protection Foils:                if fiber material is involved, the glued slip protection foils of the floor panels need to be painted in an additional process step,        the glued slip protection foils require additional and labour-intensive production steps,        the glued slip protection foils need to be produced in a separate production process, and        the sealing against gases is independent from slip protection and requires additional effort.        
Disadvantages of Rolled on Protection Material:                if fiber material is involved, the rolled on protection material of the floor panels need to be painted in an additional process step,        rolled on protection material requires additional and labour-intensive production steps, and        the sealing against gases is independent from slip protection and requires additional efforts.        
The document US 2009072086 A1 discloses an aircraft floor and interior panels where core-skin bonding is improved between honeycomb and composite face sheets (skins) by applying a polyamide and/or rubber-containing adhesive to the edge of the honeycomb prior to bonding. Edge coating of the honeycomb allows one to reduce panel weight without reducing the performance parameters that are required for different types of aircraft floor and interior panels.
The document US 2006138279 A1 discloses an aircraft floor panel for installation in a to-be-heated area of an aircraft. The panel comprises a panel-supporting level, a heat-generating level, and an upper level having an upper surface that forms the uppermost surface of the panel. A thermally conductive layer within the upper level comprises strength-imparting elements embedded in a matrix. This layer provides the primary impact-resistance for the panel and also serves as its heat-distributing layer.
The document US 2007102239 A1 discloses an aircraft floor panel comprising a honeycomb core element having an upper core surface, a lower core surface, and a core thickness. An upper face sheet assembly is mounted to and seals the upper core surface and includes at least one upper material sheet impregnated with an upper epoxy resin. A lower damping face sheet assembly is mounted to and seals the lower core surface and includes at least one lower material sheet infused with a highly damped lower epoxy resin. The lower damping face sheet assembly dampens vibrational noise.
The document WO 2006122749 A1 discloses a composite structure which comprises at least two layers. A first layer consists at least partially of a thermosetting resin and a second layer consists at least partially of an elastomer that is provided with a cross-linking agent. The at least one first layer consisting at least partially of a thermosetting resin and the at least one second layer consisting at least partially of an elastomer that is provided with a cross-linking agent are joined by a common heat treatment or another cross-linking treatment in one step. Said composite structure is used as a light weight vibration damper for interior panelling of a vehicle.
It is an objective of the invention to provide for an air vehicle with a slip protecting and gas sealing composite floor inside a fuselage that is adaptable to different requirements concerning slip protection for persons and material as well as sealing against gas penetration. It is a further objective of the invention to provide for an air vehicle with a slip protection of the floor for different soiling types, such as water, snow/ice, soil particles etc. . . . It is a still further objective of the invention to provide for an air vehicle with a floor structure as light as possible. It is a still further objective of the invention to provide for an air vehicle with a floor structure resistant against crash, hard impacts, and abrasion caused by careless loading/unloading of material.
The solution to this objective is provided with an air vehicle with a slip protecting and gas sealing composite floor inside a fuselage, the composite floor including at least one profiled elastomer layer provided at its bottom side with a cross-linking agent, one or n-layers of a further component or a variety of further components and partially thermosetting resin covered by the profiled elastomer layer, a honey comb layer and one lower layer or lower n-layers of the further component or a variety of further components and partially thermosetting resin, the honey comb layer being sandwiched between the n-layers and the lower n-layers. Advantageous embodiments of the invention are provided with the subclaims.